Users should be aware that in some of the data files, there is an error in the parameter Orbit_Start_Time_UT. When the error occurs, the symptom is that the yyyymmdd part of Orbit_Start_Time_UT refers to the day the orbit strip finished, rather than the day it started. The error only occurs when the orbit crosses midnight UT, and only on some of these orbits. Whether the error occurs depends on the time between the midnight crossing and start of data collection, so it occurs much more often in the SH than in the NH. This error will be corrected the next time the data are reprocessed. Until then, users may refer to ascii files that list the affected orbits in the NH (here) and SH (here). No PMC data are affected by this error; it is only in the Orbit_Start_Time_UT variable.